Four isostructural [Ni2Ln2(CH3CO2)3(HL)4(H2O)2]3+ (Ln3+=Dy (1), Tb (2), Ho (3) or Lu (4)) complexes and a dinuclear [NiGd(HL)2(NO3)3] (5) complex are reported (where HL = 2-methoxy-6-[(E)-2′-hydroxymethyl-phenyliminometh-yl]-phenolate). For compounds 1-3 and 5, the Ni2+ ions are ferromagnetically coupled to the respective lanthanide ions. The ferromagnetic coupling in 1 suppresses the quantum tunnelling of magnetisation (QTM), resulting in a rare zero dc field Ni-Dy single-molecule magnet, with an anisotropy barrier Ueff of 19 K.